Help with compute attribute logic for “Vehicle Stop” alarm

Hi all,
I am writing a compute attribute for when the engine is on and the speed is below 1. I want the output to trigger an alarm saying “Vehicle Stop.”
My current logic is:

speed < 1 && ignition ? "Park" : null

But it doesn’t work — the alarm value remains blank.
Can someone please help me correct it?
Thanks
Malien

It looks correct to me.

Hi Anton,

Thank you for your quick response earlier!
I tested the logic, and it works as expected when I run it directly. However, when I view the result through the popup menu, the Alarm value appears blank.
Here’s the logic I’m currently using:

(ignition && speed < 1) ? "Park" : "test"

The computed attribute shows the correct result when evaluated normally, but inside the popup, the output doesn’t display. It seems that the null value might be causing the field to show blank in the popup view.
Could you please help me identify what’s causing the Alarm value to appear blank in the popup, even though the logic itself works?
I’ve also attached an image to help illustrate the issue.
Thank you in advance for your help!

Popup Menu

This probably means you have some other computed attribute that clears the value.

Hi Anton,
Thank you for the reply. I’ve checked, and I have only one compute attribute — there isn’t any other attribute that could be clearing the value.
Could there be another reason why the Alarm value appears blank in the popup?

Best regards,

Have you linked the attribute? Have you waited enough? Why did you remove the brackets around the boolean expression?

Thanks for the reply, Anton. I’ve linked the attribute, waited, and added the brackets as well. But Alam is still blank.

Well, that's not possible. You're definitely missing something.